Nanostructured thin films as surface-enhanced Raman scattering substrates (original) (raw)

Differently shaped metal nanoparticles for the enhancement of the Raman response

2011 13th International Conference on Transparent Optical Networks, 2011

This contribution is aimed at describing the most recent activity carried out in the labs of ISC-CNR, Florence concerning preparation and spectroscopic investigation of Au and Cu nanoparticles of different dimensions and morphology, with particular focus on the properties of enhancement of the Raman response of molecular adsorbates. In this framework, we also studied both theoretically and experimentally, metal nanostars, whose morphology can be tuned in a controlled way, so that they are expected to behave as SERS active material from 500 up to 1200 nm.

Surface-enhanced Raman scattering: a new optical probe in molecular biophysics and biomedicine

Theoretical Chemistry Accounts, 2010

Sensitive and detailed molecular structural information plays an increasing role in molecular biophysics and molecular medicine. Therefore, vibrational spectroscopic techniques, such as Raman scattering, which provide high structural information content are of growing interest in biophysical and biomedical research. Raman spectroscopy can be revolutionized when the inelastic scattering process takes place in the very close vicinity of metal nanostructures. Under these conditions, strongly increased Raman signals can be obtained due to resonances between optical fields and the collective oscillations of the free electrons in the metal. This effect of surface-enhanced Raman scattering (SERS) allows us to push vibrational spectroscopy to new limits in detection sensitivity, lateral resolution, and molecular structural selectivity. This opens up exciting perspectives also in molecular biospectroscopy. This article highlights three directions where SERS can offer interesting new capabilities. This includes SERS as a technique for detecting and tracking a single molecule, a SERS-based nanosensor for probing the chemical composition and the pH value in a live cell, and the effect of socalled surface-enhanced Raman optical activity, which provides information on the chiral organization of molecules on surfaces.